1. Field of the Invention
This invention relates to multi-cell partitions used as separators for articles in boxes and the like.
2. Description of the Prior Art
As is well known, partition assemblies are used to divide the interior of a container into cells for goods, such as are packed in bottles, to protect them from damage in shipment. Also, it has been recognized that prior art partition assemblies lack desired stability in that cell walls formed by the ends of assembly strips are readily bent, deflected or distorted to interfere with loading the goods for shipment. For example, in U.S. Pat. No. 4,000,845 for "Partition Assembly and Partition Strips Therefor," issued Jan. 4, 1977, there is delineated the cause of such problem, viz., the strips have spaced slots in one edge which divide the strips into sections, and for each strip all but one section has a tab projection at such one edge which extends into the slot, and all such projections extend in the same direction. Thus, in an assembly of such interlocked strips, in which each tab extends into a notch or hole of another strip, the end sections are not locked and can curl from the vertical so as to prevent ready insertion of goods in the affected cells, all to the disadvantage of expensive down time on automatic loading equipment due to jamming.
The solution in the aforementioned patent takes the same approach as in earlier art, e.g., U.S. Pat. No. 658,930 for "Cell-Case Machine," despite differences in detail of tab shaping. Such solution is stated to be the reversing of the tab at one end of each strip so that the tab is removed from the section next to the end section that had none, and providing such end section with a tab that faces in the direction opposite to the other tabs.
By thus leaving an intermediate section on each strip without any supporting tab projection, the solution arrived at by the aforementioned patents merely shifts the problem from the end section of each strip to another location. In U.S. Pat. No. 4,000,845, it was concluded that the problem was less critical for an intermediate section than for the end section.
However, it is clear that the problem is still critical. The unsupported intermediate sections still curl over from the vertical for the same reasons as did the previously unsupported end sections. For example, the caliper or thickness of the partition strips occasionally cause an unsupported segment to bend from the vertical, as where the strips are thin and the partition height is relatively great as in forming cells for tall items. Also, the cupping effect of the paper products of which the strips are made is more pronounced as the strips get thinner, as happens when designing containers of smaller girth which will still hold the same size and number of items as previous containers. For such a smaller container to hold the same size and number of items, the partition assembly must accommodate the smaller space by use of much thinner partition strips. In such case, unsupported segments in relatively short and medium height partitions are also subject to curl from the vertical. Also, such tendencies are aided where stacks of such partitions in collapsed condition are stored for a time in extreme humid or dry environments before they are unpacked for use.
Despite such criticality, no solution has heretofore been available beyond that of shifting the location of an unsupported section of each strip from the end to an intermediate section. Since the problem is still present and apparent, those working in the field of partition design have accepted as fact that unsupported partition strip sections at some location on each strip must be tolerated.